It depends on the case, but an easy way to emit progress indicators in our system is to make the long-running service a generator. It looks like this: g =

It depends on the case, but an easy way to emit progress indicators in our system is to make the long-running service a generator. It looks like this: g = wym('/email') #=> Generator(id=<...>) g.on('value', (v) -> ... ) and /email looks like: function next(inp) { ... } return generator(next); Sending values in uses a slightly different syntax, and manually walks the generator through. :) A more trivial way is to pass in a callback for the service (we call them routes) to send its updates back to, but this requires more code to send values in. Edit: to be clear, using a Generator as above isn't very microservice-ey and will trigger our framework to start tracking local state to keep the generator around, which it will auto-free when it believes it can. This is a necessary evil with any long-running code, though. Better is to break up the code so that it may be called multiple times to progress state and returning generator('/someRoute') if possible. :P